1. Field of the Invention
The present invention relates to a power source circuit shutoff device for implementing connecting and disconnecting (shutoff) of a power source circuit by operating an operation lever.
2. Description of the Related Art
In order to secure operation safety for maintenance and the like of an electric system, a power source circuit shutoff device (service plug) capable of shutting off energization between a power source and a load is installed to an electric car or a hybrid car. As the power source circuit shutoff device, one having a structure in which operating an operation lever can mate and separate connector housings with and from each other with a small operational force is proposed (see Japanese Patent Unexamined Publication No. 2009-181895 (Patent Literature 1)). A conventional example of this type of power source circuit shutoff device is shown in FIG. 1 to FIG. 5.
In FIG. 1 to FIG. 5, a power source circuit shutoff device 100 is provided with a base housing 102 and a lever housing 120 which is mated with and separated from the base housing 102. The base housing 102 has a first mating wall 104 in a form of a frame. The inner portion of the first mating wall 104 is formed into a housing mating chamber 105. The upper face of the housing mating chamber 105 is open. A pair of first terminals (not shown) are disposed in the housing mating chamber 105. One of the pair of first terminals is connected to a battery while the other of the pair of first terminals is connected to a load. A pair of cam pins 107 are protrudingly provided on respective side faces of the first mating wall 104.
The lever housing 120 has a second mating wall 122. The second mating wall 122 has such a dimension that can be slidably mated with and separated from the housing mating chamber 105 in the first mating wall 104. A pair of second terminals (not shown) are protrudingly provided inside the second mating wall 122. The pair of second terminals are conductive with each other via, for example, a fuse.
Further, an operation lever 140 is supported to the lever housing 120 so as to be rotatable around a support shaft 124. The operation lever 140 rotates between a vertical position (positions in FIG. 2 and FIG. 3A) and a horizontal position (positions in FIG. 1 and FIG. 4). The operation lever 140 is provided with a pair of cam grooves 143 in positions bilaterally symmetrical. Each cam groove 143 has such a configuration that the distance from the support shaft 124 to the cam groove 143 becomes gradually shorter from an inlet portion 143a toward an inner side of the cam groove 143.
In the above structure, the power source conduction operation of the power source circuit shutoff device 100 will be explained. As shown in FIG. 2, the operation lever 140 is set in a position perpendicular to the lever housing 120. And the second mating wall 122 of the lever housing 120 is aligned with the housing mating chamber 105 of the base housing 102. As shown in FIG. 3A, the second mating wall 122 of the lever housing 120 is inserted into the housing mating chamber 105 of the base housing 102. Then, the second mating wall 122 is inserted to a position where the cam pin 107 is inserted into the inlet portion 143a of the cam groove 143 of the operation lever 140. This sets the base housing 102 and the lever housing 120 in a lever mating start position. In the lever mating start position, the first mating wall 104 and the second mating wall 122 are brought into a partly overlapping state.
Next, the operation lever 140 is rotated to the horizontal position (in the direction of an arrow L in FIG. 3). Then, the cam pin 107 moves within the cam groove 143 and a mating force is operated between the base housing 102 and the lever housing 120 to thereby mate the second mating wall 122 gradually deeper into the housing mating chamber 105.
As shown in FIG. 1 and FIG. 4, when the operation lever 140 is rotated to the horizontal position, the first mating wall 104 and the second mating wall 122 are brought into a lever mating completion state. The terminals (not shown) of the base housing 102 and the terminals (not shown) of the lever housing 120 start contacting each other in the mating midway position and are brought into a proper contact state in the lever mating completion position. The power source circuit is brought into a conduction state.
Further, the power source shutoff operation of the power source circuit shutoff device 100 is implemented by reversely operating the operation lever 140. That is, the operation lever 140 in the horizontal position is reversely rotated to the vertical position. Then, the cam pin 107 moves within the cam groove 143, and a separating force is operated between the base housing 102 and the lever housing 120 to thereby move the second mating wall 122 gradually in a direction separated from the housing mating chamber 105. The terminals (not shown) of the base housing 102 and the terminals (not shown) of the lever housing 120 stop contacting each other from the mating midway position and are brought into a non-contact state with the lever 140 in the vertical position. The power source circuit is brought into a non-conduction state.